Support device for a seat, in particular for a vehicle

ABSTRACT

A device adapted to permit a fine and precise adjustment in height of the front part of the cushion of a seat independently of the adjustment in the longitudinal direction of the seat. The device comprises a rack to which is pivoted a link and a stop pawl mounted to pivot about an axis on a support fixed to the floor. A mechanism which locks the pawl in engagement with the rack comprises a lever which effects successively in the course of the same travel the unlocking of the pawl and its disengagement from the rack.

United States Patent Barriere SUPPORT DEVICE FOR A SEAT, IN PARTICULARFOR A VEHICLE Inventor: Alain Barriere, Montbeliard, France Assignees:Automobiles Peugeot, Paris; Regie Nationale DesUslnes Renault,Billancourt, France Filed: Nov. 4, 1970 Appl. No.: 86,701

Foreign Application Priority Data Dec. 2, 1969 France .Q ..6941569 U.S.c1. .;...248/37l, 248/419, 297/328 Int. Cl. ..B60n 1/02 Field 61 Search..248/371, 361, 397, 407, 408, 248/409, 384, 378, 394, 395, 396, 157,419,

References Cited UNITED STATES PATENTS 8/1945 Watter ..297/328 Berecki..248/421 2,527,905 10/1950 2,594,882 4/1952 DeRose ..248/394 3,049,3308/1962 Coans et a1. ..248/419 3,198,575 8/1965 Hawkins ..297/3283,327,985 6/1967 Levitetal ..248/408 FOREIGN PATENTS OR APPLICATIONS1,052,825 9/1953 France ..248/409 Primary Examiner-Marion Parsons, Jr.Attorney-Burns, Doane, Swecker & Mathis [5 7] ABSTRACT A device adaptedto permit a fine and precise adjustment in height of the front part ofthe cushion of a seat independently of the adjustment in thelongitudinal direction of the seat. The device comprises a rack to whichis pivoted a link and a stop pawl mounted to pivot about an axis on asupport fixed to the floor. A mechanism which locks the pawl inengagement with the rack comprises a lever which effects successively inthe course of the same travel the unlocking of the pawl and itsdisengagement from the rack.

4 Claims, 4 Drawing Figures PATENTEnAus 11972 3.680 821 sum 1 [1F'2SUPPORT DEVICE FOR A SEAT, IN PARTICULAR FOR A VEHICLE The presentinvention relates to seats, in particular for vehicles. I

It is particularly important for obvious reasons of safety to improve asfar as possible the driving position of the driver of the vehicle toreduce fatigue. Consequently, vehicle seats are. usually mounted in suchmanner as to be adjustable longitudinally, in height and in inclination.

Seats are known in which the support device comprises an adjustable rearsupport and a front support constituted by at least one link pivoted tothe seat and floor. It will be understood that when the seat is shiftedin the longitudinal direction, the upper end of the link connected tothe seat describes an arc of a circle which affects the height of thefront part of the seat. However, in this case, the two movements ofadjustment, namely the longitudinal and vertical movements, cannot beeffected independently of each other and for each longitudinal positionof the seat there is a corresponding height and a correspondinginclination of the seat cushion. 1

Other devices are known in which such an independent adjustment is madepossible by the provision, for the lower pivot pin of the link, of anaperture whose height is substantially greater than the diameter of thepin and in which a withdrawable finger element defines two possiblelocations for said pin respectively in the lower part and upper part ofsaid aperture. This mechanism therefore permits a selection between onlytwo possible levels for the front part of the seat independently of thelongitudinal position of the seat.

In another support device there are provided two or three possibleapertures at different levels for one of the pivot pins of the supportlink, but in this case, to modify the adjustment, it is necessary todisengage the pin from one of the apertures and place it back inposition in one of the other apertures. This is hardly practical andentails getting off the seat and even leaving the vehicle.

In addition to their aforementioned drawbacks, the last two devices havethe essential drawback of affording only a very limited number ofpossible positions so that the differences in level between two adjacentpositions are necessarily large and/or the overall range of adjustmentis very limited.

The object of the invention is to provide adevice which does not havethese various drawbacks.

The invention provides a seat support device, in particular for avehicle, comprising rear support means and front support means, thefront support means having at least one link connected to the floor ofthe vehicle by a mechanism which is adjustable in height, said mechanismcomprising two complementary toothed or notched elements one of which isconnected to the seat and the other to the floor, guide means for theelement connected to the seat, and shifting and locking means fordisconnecting or maintaining said elements engaged so as to allow eitheran adjustment in height or the locking of the element connected to theseat in the selected position by the element connected to the floor.

One embodiment of the invention will now be described with reference tothe accompanying drawings, in which:

FIG. 1 is a perspective view of a vehicle seat equipped with a deviceaccording to the invention, and

FIGS. 2, 3 and 4 are sectional views of the device in three differentpositions.

FIG. 1 shows by way of example a seat S having a cushion or seat properA and a backrest D. This seat is longitudinally adjustable by a slidingmotion in rear slideways G and.a swinging motion of a front link B.

The mechanism according to the invention, which permits the front partof the cushion to be adjusted in height and therefore permits theinclination of the cushion to be adjusted, comprises a support member 1integral with the floor P of the vehicle, a rack 2 and a withdrawabletoothed pawl 3. The support 1 has two parallel wing portions la whichare interconnected by a transverse wall 1b and terminate at their freeedges in two inwardly extending flanges 4. The link B is pivoted by aspindle or pin 5 to the rack 2 which has two vertical grooves 6receiving the vertical flanges 4 of the support 1.

The stop pawl 3, whose teeth have a shape complementary to that of theteeth of the rack, is rotatably mounted on the member 1 by journal means7 having an axis X-X parallel to the pivot axis of the link B. Thejournal means 7 can be a pin extending transversely between the wingportions la, or two aligned journals.

The shifting and locking mechanism comprises a cranked lever 8 having atone end a knob 8a and at the other end a straight portion 8b which hasan axis Y-Y (FIG. 2) and extends through two aligned apertures 9 ofoblong shape formed in the wing portions la of the support member. Thegeneral shape of the apertures is an arc of a circle roughly centered onthe axis X-X. The portion 8b is rotatable in an aperture or bore 10provided in the center part of the'pawl 3. It carries a crank consistingof an arm 11 and a finger portion 12 which is received in an opening 13formed in one of the wing portions of the member 1. The opening 13 issubstantially L-shaped, one of the branches 13a of the L shaped opening13 is centered on the axis Y-Y when the pawl is engaged with the rack(FIG. 2) and the other branch 13b is centered on the axis X-X.

A spring 14 acts between the fixed support 1 and the crank 11 so as tomaintain the latter in the position shown in FIG. 2, that is, in theposition for locking the stop pawl 3.

The operation of the support device according to the invention will nowbe explained in detail with reference to FIGS. 2, 3 and 4, assuming thatthe seat is maintained in a given longitudinal position by a lockingdevice which has not been shown since, strictly speaking, it forms nopart of the invention.

When the device is in the locked position (FIG. 2), the teeth of thestop pawl 3 are engaged in the teeth of the rack 2 and thus lock thelatter and the seat in a given position. Indeed, disengagement of theteeth, by rotation of the pawl 3 about the axis X-X, cannot occur sincethe portion 8b of the lever is held stationary by the crank 11 whosefinger portion 12 is retained by the upper edge of the branch 13a of theopening 13 which is concentric with the axis YY. No unlocking reactioncan therefore occur.

To adjust the seat in height, the shifting lever 8 must be shifted fromthis locked position in the direction of arrow F in opposition to theaction of the spring 14.

This causes the crank 1 l to rotate about the axis Y-Y. The fingerportion 12 moves along the branch 13a of the opening 13 and finallyoccupies the position shown in FIG. 3.

The device is then locked and, when the control lever 8 is continued tobe shifted in the direction of arrow F the finger portion 12 is guidedtowards the upper end of the branch 13b which is roughly centered on theaxis XX and the portion 8b moves in the apertures 9 towards the left (asviewed in the drawing) and in so moving, shifts the pawl 3 anddisengages it from the rack 2. In this way, the position shown in FIG. 4is reached in which the pawl 3 is completely disengaged from the rack 2.

If the user bears against the backrest or the cushion of the seat so asto tilt the latter, it is then possible to bring the cushion to the newdesired position. It is sufficient to release the control lever 8 forthe action of the weight of the crank 11 and lever 8a and the action ofthe spring 14 to return the assembly to the locked position shown inFIG. 2.

Thus the mere shifting of the lever 8 in the direction of arrow Fproduces, in a first stage, an unlocking of the pawl 3 then, in a secondstage, the disengagement of the pawl from the rack teeth and theunlocking of the rack 2. Moving the lever 8 in the opposite direction,results in a positive interlocking of the stop pawl and the rack andthis ensures that the rack does not accidentally become disengaged.

Further, the precision of the adjustment, defined as the differencebetween two adjacent positions of adjustment, is equal to the spacebetween two adjacent teeth of the rack or of the pawl and therefore canbe chosen as desired. Similarly, the range of adjustment can berelatively wide with respect to that obtained in known devices, the twoextreme positions of adjustment being determined in one direction by therack contacting the floor or a member secured to the latter, and, in theother direction, by the rack coming in contact with an abutment providedon the support member 1.

Although the link has been shown to be pivoted to the rack 2, it is alsopossible to reverse the functions of the two complementary toothedelements.

Having now described my invention what I claim and desire to secure byLetters Patent is:

l. A support device for a seat in particular for a vehicle having afloor, comprising rear support means and front support means, the frontsupport means comprising a support member integral with or fixed to thefloor and having two parallel wing portions defining parallel guidemeans and a transverse wall interconnecting the wing portions, a rackmember having a toothed front portion and two lateral faces providedwith two parallel guide means slidably engaging said guide means of thefixed support member respectively, link means interconnecting said rackmember and the seat, a toothed pawl member pivoted about a first axis onsaid front support means and having a toothed portion facing the toothedfront portion of the rack, and shifting and locking means forselectively disconnecting and maintaining said rack and pawl membersengaged so as to allow selectively an adjustment in height of said rackmember and the locking of said rack member with respect to the frontsupport member in a selected position.

2. A device as claimed in claim 1, wherein each wing portions of saidsupport member has a flange extending towards the flange of the otherwing portion, and the rack member has two grooves provided in itslateral faces, respectively, and slidably engaging said flanges.

3. A device as claimed in claim 1, wherein the pawl is rotatable about afirst axis between the two wing portions of the support member, saidshifting and locking means comprising a shifting lever having arectilinear portion which has a second axis parallel to said first axis,a first aperture in the pawl, two second apertures in the support memberand centered on said first axis, the rectilinear portion of the shiftinglever being rotatably mounted in the first aperture and guided in thesecond apertures, and a crank which is integral with the rectilinearportion of the shifting lever and carries a finger portion, an openingin the support member guiding the finger portion, the opening comprisingtwo branches, a first of said branches being substantially centered onsaid second axis when said rectilinear portion is in a positioncorresponding to engagement between the pawl and the rack, and a secondof said branches being substantially centered on said first axis.

4. A device as claimed in claim 3, comprising resiliently yieldablemeans for biasing the crank to a position which corresponds to theengagement and locking of the pawl with respect to the rack.

1. A support device for a seat in particular for a vehicle having afloor, comprising rear support means and front support means, the frontsupport means comprising a support member integral with or fixed to thefloor and having two parallel wing portions defining parallel guidemeans and a transverse wall interconnecting the wing portions, a rackmember having a toothed front portion and two lateral faces providedwith two parallel guide means slidably engaging said guide means of thefixed support member respectively, link means interconnecting said rackmember and the seat, a toothed pawl member pivoted about a first axis onsaid front support means and having a toothed portion facing the toothedfront portion of the rack, and shifting and locking means forselectively disconnecting and maintaining said rack and pawl membersengaged so as to allow selectively an adjustment in height of said rackmember and the locking of said rack member with respect to the frontsupport member in a selected position.
 2. A device as claimed in claim1, wherein each wing portions of said support member has a flangeextending towards the flange of the other wing portion, and the rackmember has two grooves provided in its lateral faces, respectively, andslidably engaging said flanges.
 3. A device as claimed in claim 1,wherein the pawl is rotatable about a first axis between the two wingportions of the support member, said shifting and locking meanscomprising a shifting lever having a rectilinear portion which has asecond axis parallel to said first axis, a first aperture in the pawl,two second apertures in the support member and centered on said firstaxis, the rectiLinear portion of the shifting lever being rotatablymounted in the first aperture and guided in the second apertures, and acrank which is integral with the rectilinear portion of the shiftinglever and carries a finger portion, an opening in the support memberguiding the finger portion, the opening comprising two branches, a firstof said branches being substantially centered on said second axis whensaid rectilinear portion is in a position corresponding to engagementbetween the pawl and the rack, and a second of said branches beingsubstantially centered on said first axis.
 4. A device as claimed inclaim 3, comprising resiliently yieldable means for biasing the crank toa position which corresponds to the engagement and locking of the pawlwith respect to the rack.